About now, farmers in Iowa and across the Corn Belt get itchy. As the weather warms, they start tuning plows and planters, preparing to put another crop of corn and soybeans in the ground.

Within months, the rural Midwest will largely be a sea of towering stalks filling out ears and squat bean plants putting on pods.

But this sea of biomass has unforeseen effects on Midwestern climate, a study from the Massachusetts Institute of Technology suggests – and, I would argue, contributes to global climate change.

When you’re driving past those carpeted fields this summer, you can thank them for countering higher temperatures driven by greenhouse gas emissions, but curse them for more frequent drenching, violent thunderstorms and tornadoes.

It stands to reason that agriculture – which has never been more intense or widespread in human history – is doing something to our weather. But there are bigger questions about its impact.

One of the better signs at last year’s March for Science Iowa featured dear old Darwin. Credit: Paula Mohr.

Iowans have an opportunity to hear from a hero in the battle to halt or reverse climate change.

The event is the annual Iowa City Darwin Day, actually a two-day symposium to honor Charles Darwin, the naturalist whose book, “On the Origin of Species,” posited evolution as an explanation for the diversity of life on Earth. The celebration is held every year on or around the great scientist’s February 12 birthday. This year it’s Friday and Saturday, February 23-24, on the University of Iowa campus.

Darwin Day celebrates science – particularly science that often is denigrated or attacked, such as evolution and human-caused climate change. Many of the sessions revolve around these two subjects and how to communicate about them with skeptics.

This year’s program includes a rare chance to see in person a former Iowan who has become a champion and a lightning rod on climate change.

Science backers listen to speakers during the March for Science Iowa on April 22, 2017 at the Iowa State Capitol in Des Moines.

Nearly a year ago, around 3,000 Iowans gathered on a sunny April day to support science – its role in public policy and improving the human condition – at one of dozens of marches around the world.

The March for Science Iowa, April 22 (Earth Day), united citizens, sent a message to government and provided insights into Iowa-based research. But its organizers say their dreams to continue advocating throughout the year haven’t panned out. Assembling the event left many of them exhausted. I was involved and, like others, the demands of work and family left me little time for activism. (Just look at the recent sparsity of posts to this site for evidence.)

Now, however, two of last year’s leaders are staging a revival, starting with a second event – to coincide, again, with a national March for Science. They’re also working to institute a formal structure that, with luck and hard work, could lead to a more enduring impact.